Update: Several East Coast stations defied their networks, carrying the President’s 15-minute speech live and preempting primetime shows. NBC’s WNBC and Fox’s WNYW in New York, as well as stations in Washington, D.C., Boston and Atlanta opted to dump their network feeds in favor of POTUS.

While the major commercial networks will not interrupt primetime programming to carry President Obama’s speech on immigration tonight (it’s a Thursday night, in sweeps, so they won’t preempt their biggest shows), Univision and Telemundo are committing to the story live and through the weekend. It will also be available live on cable news networks and PBS. In the Mountain Time Zone, it falls to the local stations whether or not to carry the speech.

Locally, CBS4, 7News Fox31 and 9News will carry the speech at 6 p.m.

Univision News intends to bring audiences “every detail surrounding President Barack Obama’s plans for issuing executive orders on immigration,” starting at 4:30 p.m. locally, with anchor Jorge Ramos leading coverage live from the White House. ““Noticiero Telemundo” will do the same, with anchors José Díaz-Balart and María Celeste Arrarás at the White House. The speech is scheduled for 6 p.m. locally.

On Univision, the address will preempt the 2014 Latin Grammy Awards, “an annual special that reached 9.8 million viewers on the Univision Network last year.”

On Sunday, the public affairs show, “Al Punto” (To the Point), hosted by Jorge Ramos, will be dedicated to the subject; a special edition of the award-winning newsmagazine “Aquí y Ahora” (Here and Now) will present a panel of experts to answer viewers’ questions on the subject, hosted by Teresa Rodríguez and María Elena Salinas.

The other networks have given up any obligation to cover Presidential announcements — and the White House knows this. Why else announce the speech via Facebook?

Joanne Ostrow has been watching TV since before "reality" required quotation marks. "Hill Street Blues" was life-changing. If Dickens, Twain or Agatha Christie were alive today, they'd be writing for television. And proud of it.